1. Field of the Invention
The present invention relates to a communication system by electrostatic coupling and electromagnetic induction, which is a wireless communication system used for short/medium distance which is in a range constantly visible in a normal environment, and which, when information to be transmitted by the system has properties different in quantity or quality, efficiently transmits such various pieces of information from a base station to a terminal station. In particular, the present invention relates to a technology which relaxes an alignment requirement between the base station and the terminal station which are components of such a system, and is effective when applied to a-technology of efficiently transmitting such various pieces of information from the base station to the terminal station.
2. Description of the Related Art
JP 05-342426 A discloses a technology for information cards such as IC cards and memory cards, in which data is written through electric-field coupling, and is read through impedance changes of a coil. Further, JP 11-134450 A discloses a technology for non-contact IC cards, in which power transmission and PSK signal transmission are performed through electromagnetic induction, and non-contact signal transmission is performed through electrostatic coupling.